Portable shavers provided with rechargeable batteries and a device to recharge them are known. There are two ways to recharge the rechargeable batteries contained in the shaver. One of them is to supply electrical power to the shaver through an electrical cord, while the other is to do the same by plugging sliding plug blades protruded from a body housing of the shaver into a receptacle arranged on a wall of a house. However, in the former case, the electrical cord is always necessary for recharging, while in the latter case the shaver can not be used during recharging of the battery of the shaver or when the batteries are not recharged enough.
To solve these problems a shaver in which the sliding plug blades for recharging are provided and the electrical cord can be also used, has been proposed. This kind of a shaver is disclosed in (Japan) Utility Model Laid-open No. 1-40,134, which will be explained with reference to FIGS. 9 and 10.
FIGS. 9 and 10 show the lower part of body housing 1 in a conventional shaver. Fixed terminal 21 with power inlet pin 5 into which electrical cord 20 is plugged, is arranged on one side of body housing 1, while slots 28 from which sliding plug blades 4 can be extracted for recharging are arranged on the other side. Two sliding plug blades 4 are fixed on both sides of plug support 22 which is made of insulating material. Recess 23 is formed at the central portion of the plug support 22, which recess accommodates operating knob 24 together with spring 29. There are formed lock grooves 25a, b to be engaged with the operating knob 24 at the base of the body housing 1. Sliding electrode 27 connected to fixed terminal 21 and sliding electrode 26 connected to electric circuits of the shaver are in contact with the top of the sliding plug blades 4.
FIG. 9 shows the situation in which the sliding plug blades 4 are retracted in the body housing 1 (an electrical cord mode). In this situation electrical power is provided to the shaver via the electrical cord 20 connected to power inlet pin 5, which power is provided to electric circuits through the sliding electrode 27, the sliding plug blades 4 and the sliding electrode 26.
FIG. 10 shows the situation in which the operating knob 24 pushed upwardly by a finger, so that a lock state with lock groove 25a is released, is being moved toward lock groove 25b. When the operating knob 24 is engaged with lock groove 25b, the sliding plug blades 4 are pushed out from slots 28, which enables one to recharge the shaver by the sliding plug blades 4 plugged into a power receptacle (a plug blade mode). In this case, since the sliding electrodes 27 are in contact with plug support 22 made of insulation material, the electric circuit between fixed terminal 21 and sliding electrodes 26 is cut off, so that electrical current is provided to the shaver not by electrical cord 20 but by the sliding plug blades 4.
The above-mentioned rechargeable shaver may cause a problem that a user receives an electric shock, when he happens to touch the sliding plug blades 4 with a metal piece or the like through an opening of the body housing 1 which is arranged for a path where operating knob 24 moves. Furthermore, since the distance between the top of sliding plug blades 4 and the outside surface of slot 28 is only about 0.5 mm when the sliding plug blades 4 are retracted within body housing 1, that is, under the electrical cord mode, a user may receive an electric shock when his finger touches the top of sliding plug blades 4 through the slot 28 when he grips the shaver.
In addition, switching circuits are necessary in order to avoid the situation wherein current is provided to power inlet pin 5 so that a user receives an electric shock if he touches power inlet pin 5 while the shaver is being recharged by the sliding plug blades 4, that is, under the plug blade mode.